猪链球菌2型和9型广东分离株的病原特性  

Pathogenic characteristics of Streptococcus suis type 2 and type 9 isolated from Guangdong province

作　　者：余炜烈[1] 李春玲[2] 王贵平[2] 陆承平[1] 

机构地区：[1]南京农业大学动物医学院,江苏南京210095 [2]广东省农业科学院兽医研究所,广东广州510640

出　　处：《中国兽医科学》2007年第8期650-654,共5页Chinese Veterinary Science

基　　金：2005年关键领域重点突破项目(2005A10905006)

摘　　要：2005年夏秋季从广东地区9例病猪中分离到2株猪源链球菌,均呈链球菌的特征形态,α溶血,生化试验结果相似,且都不与A^G链球菌群特异性血清发生凝集。经PCR及测序鉴定,一株为猪链球菌2型,另一株为猪链球菌9型。2型分离株的3个毒力基因均为阳性(sly+epf+mrp+),但对小鼠的毒力较低,2/10小鼠在接种细菌后第6~15 d发病致死,细菌在小鼠中的带菌时间至少15 d;9型分离株3个毒力因子均阴性(sly-epf-mrp-),但对小鼠有较强毒力,9/10小鼠在接种细菌后5 d内发病死亡,对小鼠的半数致死量为1.70×106CFU。表明广东地区致病性猪链球菌不仅存在2型,而且还有9型。Two strains of pathogenic bacteria were isolated from 9 dead pigs in Guangdong Province between summer and autumn in 2005. The morphological and culture characteristics indicated that the isolates belonged to the genus Streptococcus. The biochemical characteristics was similar between the 2 isolates,and the isolates were not able to be agglutinated by the Lancefield group A-G latex diagnostic kit. Serotype-specific PCR revealed that one of the isolates represented Streptococcus suis type 2 and the other represented S. suis serotype 9. Moreover,genetype sly^＋ epf^＋ mrp^＋ was detected in the isolate of type 2, and the isolate was low in virulence and was able to infect mice（2/10） on day 6-15 postqnoculation. Genetype sly^-epf^-mrp^- was detected in the isolate of serotype 9,but the isolate was highly virulent to mice（9/10） and its LD50 was 1.70×10^6 CFU. The results demonstrated that S. suis type 2 and 9 were able to cause swine streptococcosis in Guangdong province.

关 键 词：猪链球菌2型 猪链球菌9型 病原特性 PCR 

分 类 号：S852.611[农业科学—基础兽医学]